My step-daughter was born in Canada,while her parents were visiting there. She has lived in Minnesota her whole life and has a Social Security Card and had a Minnesota drivers license. Now she has moved to Tennesee and is trying to get a Tennesee drivers license, but they are telling her she is not a US citizen. How is it possible for her to have a SSN if she is not a citizen, and how can she prove that she is?

Not enough information.

From the information provided, she is a Canadian citizen. Are her biological parents US citizens? If they are, did they register the birth with the US consulate?

She will need to apply for a US passport and prove up her parents citizenship and physical presence in the US. Call the US passport office and you should consult with an experience immigration attorney.

A SSN does not prove up US citizenship, it is only for paying into social security, so anyone working in the US generally will have a SSN.

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